If you have a panini press, it definitely makes the job easier, but if you do not, it's ok - you can make a panini in a grill pan, or you can make a toasted (or grilled) grape and cheese sandwich.

Heat the panini press or the grill pan or skillet over medium heat.

Start by buttering each slice of bread on one side.

Slice the grapes in half.

Lay the bread buttered side down in the panini press or the skillet and place a slice of cheese on the bread.  Top with the sliced grapes and the arugula.  Place the top bread, buttered side up on top of the arugula.  Close the panini press and let the sandwich cook for about 3-4 minutes until golden brown and the cheese is melted.

If using a skillet or grill pan, place a 2nd pan or skillet on top of the sandwich to press it down slightly.  Cook for 4 minutes, then remove the skillet and carefully flip the sandwich using a spatula.